A lip cream with special propolis extract GH 2002 at a concentration of 0.5% (199 patients) was tested against aciclovir 5% (198 patients) in the treatment of episodes of herpes labialis under double-blind conditions. Upon inclusion, all patients were in the vesicular phase. Application was five times daily of approximately 0.2 g of cream to the entire upper and lower lip. The primary parameter was the difference in time between groups to complete encrustation or epithelization of the lesions. Secondary endpoints were the course of typical herpes symptoms (pain, burning and itching, tension and swelling), the global assessment of efficacy and the safety of application. The predefined clinical situation was reached after a (median) 3 days with propolis and 4 days with aciclovir (p < 0.0001). Significant differences in favor of propolis were also found for all secondary parameters. No allergic reactions, local irritations or other adverse events occurred.